import java.applet.*;
import java.awt.*; 
public class Graphica extends Applet implements Runnable{
  Graphics g;        
  Color bgColor;     
   
  int TOPX=100;      
  int TOPY=10;       
  int X = 0;   
  int Y = 0;   
  int quant=50;   
  float L=150;   
  double Xm=100;   
  float Tm=100;   
  long T=0;      
  double kzat=0.999; 
 
 public void init()

 { 
   g = getGraphics(); 

   bgColor = new Color (255,255,255);
   setBackground(bgColor);
    get_coordinates();
 }

{
    (new Thread(this)).start();
}
public void run()
    {
      while (true)
        {
           get_coordinates();      
           repaint();               
           T=T+quant;              
           Xm=Xm*kzat;
           try 
              {
                Thread.sleep(quant);  
             }
            catch (InterruptedException e)
            {
            }
           }
     }
            
            
            void get_coordinates()
{
        double S;
        S=Xm*Math.cos(Math.sqrt(9.8/L)*(T/Tm));
        //Liigub vastavalt määrustele
        //X=Xm*cos(wt);
        //t=T/1000 (aeg)
        // w=sqrt(g/l)
      
        
        double a;
        a=(Math.asin((S/2)/L))*2;
        X=(new Double(L*Math.sin(a)).intValue())+TOPX;
        Y=(new Double(L*Math.cos(a)).intValue())+TOPY;       
}
public void paint(Graphics g)
 {
   g.setColor(Color.black);  
     g.drawLine(TOPX-40,TOPY,TOPX+40,TOPY); 
     
     g.setColor(Color.green);
     g.drawLine(TOPX,TOPY,X,Y);           
    
     g.setColor(Color.red);     
     g.fillOval(X-10,Y-10,20,20);           
  }  

     
private void initComponents () {
    setLayout (new java.awt.BorderLayout ());

}


}